How to account for memory in Redhat Linux

[Basheer_2]

Hello,

RH ES ver 3.5,

#free -m
total used free shared buffers cached
Mem: 6015 5984 30 0 270 3032
-/+ buffers/cache: 2681 3333
Swap: 4094 2439 1655

from this,
Total RAM = 6GB, used = 5.9GB,Free = 30MB

Memroy used by all processess
ps -aux|gawk '{print $4}'|awk '{print s+=$1}'

total %MEM = 51.3

from free -m it says only 30MB free, ps - aux shows, only 51.3 % is used, so

Where is the restof the memory ?

Thanks

ps -aux|gawk '{print $4}'|awk '{print s+=$1}'

[Stuart Browne]

Buffers and Cache.

Speeds up all your Disk IO.

[Srimalik]

Linux dynamically manages the buffer cache.

It stores a lot of data read from the hard disk in RAM.

So total memory consumption = memory taken by process + memory given to caches

The amount of mem given to cache is dynamic i.e when you start a new process the buffer cache will be shrinked and new process will be given that memory.

This all is done to increase the speed of system.

[Srimalik]

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